• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Concentration maxima of methane in the bottom waters over the Chukchi Sea shelf: implication of its biogenic source

    2022-10-19 05:38:04LIYuhongZHANGJiexiaYEWangwangJINHaiyanZHUANGYanpeiZHANLiyang
    Advances in Polar Science 2022年3期

    LI Yuhong, ZHANG Jiexia, YE Wangwang, JIN Haiyan, ZHUANG Yanpei & ZHAN Liyang*

    Concentration maxima of methane in the bottom waters over the Chukchi Sea shelf: implication of its biogenic source

    LI Yuhong1, ZHANG Jiexia1, YE Wangwang1, JIN Haiyan2, ZHUANG Yanpei3& ZHAN Liyang1*

    1Key Laboratory of Global Change and Marine–Atmospheric Chemistry (GCMAC) of Ministry of Natural Resources (MNR), Third Institute of Oceanography (TIO), MNR, Xiamen 361005, China;2Laboratory of Marine Ecosystem and Biogeochemistry, Second Institute of Oceanography, MNR, Hangzhou 310012, China;3Polar and Marine Research Institute, Jimei University, Xiamen 361021, China

    Chukchi Sea shelf, methane, sources, nutrient, organic carbon, organic matter

    1 Introduction

    Methane (CH4) is the most abundant hydrocarbon in the atmosphere and plays an important role in radiation balance and atmospheric chemistry (Cicerone and Oremland, 1988). The atmospheric CH4concentration has been increasing steadily, with a modern-day level of 1.91 ppmv (parts per million by volume), which is more than twice the preindustrial value of 0.71 ppmv (IPCC, 2007). CH4accounts for 15%–20% of the radiative forcing, and the elevated CH4concentration has further intensified greenhouse effects (Chappellaz et al., 1993). To understand the dynamics of atmospheric CH4, various sources of natural CH4need to be constrained.

    Oceans are net sources of atmospheric CH4(Bange et al., 1994; Bates et al., 1996), and 6–12 Tg CH4are emitted from the global ocean per year (Weber et al., 2019). Methanogenesis, an anaerobic microbial process mediated by archaea, amounts to approximately 0.1% of ocean primary productivity, is most prevalent in sediments with a high sedimentation rate (Henrichs and Reeburgh, 1987; Reeburgh, 2007), and is thought to dominate marine CH4emissions. However, seepages of thermogenic CH4and the breakdown of CH4hydrates may also be significant contributors to these emissions (Kvenvolden and Rogers, 2005). Recent estimates suggest that 7×105–4×106Tg CH4are stored as hydrates in the ocean (Buffett and Archer, 2004); this value is at least 2 orders of magnitude larger than the atmospheric CH4reservoir (~ 5000 Tg).

    A large amount of organic carbon is buried in Arctic Ocean sediments (Gramberg et al., 1983; Shakhova and Semiletov, 2007), which makes the Arctic Ocean a potential CH4source. The Arctic Ocean is particularly sensitive to global warming, and the effects of warming on ecosystems will be the most dramatic in the Arctic (Holland and Bitz, 2003). Recently, many studies have proposed that the Arctic shelf is an important CH4source, and an additional release of CH4might result from the temperature destabilization of gas hydrates on the shallow continental shelves in the Laptev and East Siberian Seas (Shakhova and Semiletov, 2007; Shakhova et al., 2010), Spitsbergen continental margin (Damm et al., 2005; Westbrook et al., 2009). Organic matter stored in the sediment might be mobilized onto the shelves, leading to further biogenic CH4release via methanogenesis in the White Sea and Storfjorden (Savvichev et al., 2004; Damm et al., 2007). However, the sources of CH4are still not well understood in the Arctic shelf due to the complexity of the processes involved and the difficult access to these remote regions. In the Chukchi Sea, limited research has revealed CH4accumulation in the bottom waters (Li et al., 2017; Kudo et al., 2018; Bui et al., 2019). In conjunction with13CCH4values (Fenwick et al., 2017; Kudo et al., 2022), the most likely CH4source in this region is biogenic production, resulting from the decomposition of organic carbon in the seafloor. To date, it is believed that methane from the Arctic continental shelf is dominated by thermogenic origin, with a secondary of biogenic source (Berchet et al., 2020).

    In this study, we present data for CH4in a water column over the Chukchi Sea shelf (CSS). We were able to obtain the characteristics of the vertical distribution of CH4in relation to the water mass structure. We also compare CH4with nutrient data and discuss possible processes that produce CH4in seawater.

    2 Study area and methodology

    2.1 Study area and its hydrographic setting

    The CSS is one of the largest continental shelves in the world and has high biological productivity; Pacific Ocean waters transit through the Bering Strait and enter the Chukchi Sea (Figure 1). Three main transport pathways have been identified in the CSS: the inflow of warmer, fresher Alaskan Coastal Current (ACC) waters through the eastern channel (Coachman and Aagaard, 1966; Gong and Pickart, 2015); the transport of Bering Shelf Water (BSW) through the central channel between the Herald and Hanna Shoals (Woodgate et al., 2005); and the transport of colder, saltier, more nutrient-rich Anadyr Water in the west, which tends to follow Hope Valley toward Herald Canyon (Weingartner et al., 2005). Shipboard observations were conducted on the R/Vduring the 5th Chinese National Arctic Research Expedition (CHINARE); seawater samples for CH4and otherparameters were collected along 169°E meridian (named SR section) in September 2012. The sampling depths were 5, 20, 30, 40, 50, 70, 100 m and 5 m above sea floor.

    2.2 Methods

    CH4samples were transferred to a Biochemical Oxygen Demand (BOD) bottle (250 mL), with approximately twofold overflow of the bottle volume to avoid bubbles. To inhibit biological activity, 120 μL of saturated HgCl2solution was added to the water samples. The bottles were sealed with greased stoppers that were then fixed with a clip. The sample bottles were kept in the dark at 4 ℃until transport back to the laboratory on land for analysis. Subsamples were taken following the method of Butler and Elkins (1991). The headspace method was adopted to pretreat the water samples, and high-purity N2was introduced to create an around 7 mL headspace in 50 mL preweighed bottles. After shaking for 1 h at 30.0 ℃, full equilibrium was achieved. The 5-mL gas samples were injected into an Agilent 7890A gas chromatography equipped with a flame ionization detector (FID). The CH4gas standards were provided by the National Institute of Metrology, China. There is a linear relationship between the FID signal and the CH4concentration; a single-point standard was inserted after every 12 samples to enable assessment of the drift of the FID. The precision of repeated analyses of 10 water samples was approximately 5% (Li et al., 2017).

    Figure 1 Sampling stations along the SR section (blue circles) in the CSS during the 5th CHINARE. The inflow of the Bering Strait is separated into three main branches: Anadyr Water (AW), Bering Shelf Water (BSW), and Alaska Coastal Water (ACC).

    3 Results and discussion

    3.1 Hydrology and nutrient distributions

    Due to the influence of warm and saline Pacific water and cold and fresh ice-melt water, wide temperature and salinity ranges were observed in the water column of the SR transect, with values ranging from approximately ?1.6–7.6℃ and 26.4–34.4, respectively (Figure 2). Cold and even freezing temperatures were observed in the northern bottom region, and warm water was distributed mainly in the southern surface layer. High-salinity (>32) water was present only in the bottom of the column, whereas low-salinity water (<32) water was widely distributed in the narrow surface waters. The distribution pattern of temperature was the opposite of that of salinity along the transect. Despite the change in temperature, the pattern of potential density was similar to that of salinity, which indicates that the water masses were mainly controlled by salinity. High stratifications could be observed in the distribution patterns, with the intensive dispersal of dense water masses at the bottom and vice versa.

    Physical characteristics of the water masses were identified (Figure 3), and high-temperature and low-salinity waters (T≈6℃, S≈27) on the southern surface were distinguished from BSW (Walsh et al., 1989). An extremely fresh and relatively cold water mass (T≈?1℃, S≈27) in the northern surface typically originates from near-surface ice-melt water (SIMW) (Weingartner et al., 2005). A high-salinity water with freezing temperatures (T≈0℃, S≈33) dispersed in the bottom layer is typically regarded as a portion of remnant winter-transformed water (WW) from the previous winter (Weingartner et al., 1998; Spall, 2007). In the study area, a salinity gradient generated a pronounced pycnocline at depths of 20–30 m, and vertical diffusive transport and the mixing of biogenic elements were restricted and trapped in the bottom waters.

    Figure 3 Temperature-salinity diagrams and CH4concentrations in the SR section of the CSS.

    3.2 Distributions of CH4 in the CSS

    The vertical distribution of CH4along section SR is presented in Figure 4, showing that the CH4concentrations showed marked variations; CH4in the surface waters (approximately 5 m below the sea surface) ranged from 4.6 nmol·L?1to 14.6 nmol·L?1, which were significantly higher values than the expected atmospheric equilibrium concentrations of 3.2–4.1 nmol·L?1, with saturations from 114% to 398%. This result means that surface waters in the CSS were supersaturated with CH4and could be a potential source of atmospheric CH4. In the water column,CH4concentrations ranged from 4.8 nmol·L?1to 38.8 nmol·L?1, and the maximum concentrations of CH4were distributed in the bottom waters of stations SR03, SR10, and SR11, representing CH4supersaturation of up to 962% in the dense and cold bottom waters of the CSS. The ambient dissolved oxygen (DO) of the water column ranged from 7.3 mg·L?1to 13.9 mg·L?1, with high concentrations located in the surface waters of stations SR03, SR11, SR12 and the lowest values at the bottom waters of the same stations. There were consistently high concentrations of CH4and low DO levels in the bottom waters of stations SR03, SR10 and SR11 (Figure 4, Table 1). Nutrient-rich Pacific water and sea-ice melting increase the light-stimulated primary production of ice algae andphytoplankton, maintaining high concentrations of DO in the surface and shallow depths, as well as low grazing pressure and a high flux of organic carbon settling to the seafloor (Grebmeier et al., 2006); furthermore, respiratory action consumes O2and reduces the concentration of DO in the bottom waters. In general, the distribution pattern of CH4is similar to that of salinity and potential density, with an increasing trend from the surface to bottom water (WW). Water masses are a factor controlling the gradient shape in the Chukchi Sea, suggesting that high concentrations of CH4are trapped below the pycnocline (Fenwick et al., 2017; Kudo et al., 2022); thus, the CH4concentration in surface waters is limited during the autumn stratification period (Kudo et al., 2022). The distribution of CH4showed a clear increasing downward gradient, indicating that high concentrations of CH4in near-bottom waters at these stations might correlate with the production and emission of CH4from the organic-rich sediment interface.

    Table 1 Mean (in brackets) and variation ranges of the main parameters in different water masses in the CSS

    Figure 4 Distributions of methane (CH4), methane saturations and dissolved oxygen (DO) in the SR section of the CSS.

    3.3 Sources of CH4 in the CSS

    3.4 Comparison with other areas in the Arctic Ocean

    CH4can be produced through the bacterial degradation of organic materials in sediments and subsequent release into the overlying near-bottom waters through sediment water exchange, seepages of thermogenic methane from the decomposition of hydrates, the leakage of gas, and serpentinization reactions that may occur in specific areas (Reeburgh, 2007). As this area does not apparently contain subsea permafrost or gas hydrates (Ruppel, 2015), and13CCH4values are indicative of biogenic production (Whiticar and Faber, 1986), the most likely CH4source in this region is seafloor methanogenesis resulting from the decomposition of organic carbon (Fenwick et al., 2017). In the CSS areas, the concentrations in the bottom layer were higher (up to 55.9 nmol·L?1), whereas13C values were lower (down to ?63.8‰) than in the surface layer, indicating that CH4was produced mainly by organic matter degradation in seafloor sediment via methanogens (Kudo et al., 2022). As a result, the release of CH4from the sediments into the water column results in a dome-like structure of relatively high CH4concentrations in the dense bottom water of the CSS. We summarized CH4concentrations and sources in different areas of the Arctic Ocean (Table 3) and distinguished the origin of CH4from sedimentary release. Compared to the open ocean, in the East Siberia Sea, because of a lack of sunlight and highly turbid waters, primary production is suppressed by factors of 100 to 1000, whereas the CH4levels are elevated 10-fold, which could be attributed to the thawing of the subsea permafrost and the consequentially increased permeability for CH4(Shakhova et al., 2010). In SW-Spitsbergen, CH4concentrations 2 orders of magnitude higher than the equilibrium concentrations with the atmosphere are discharged from thermogenic processes or hydrate on top of sandy and gravelly banks, with distinctly heavy13CCH4values (Damm et al., 2005). The highest concentration of CH4in the White Sea and Storfjorden was approximately 50 nmol·L?1in the bottom waters because of high accumulation rates of organic carbon (Damm et al., 2007; Savvichev et al., 2004); thus, both areas are ideal environments for the formation of biogenic methane near the sediment surface (Daniel and Jochen, 2005). For dome-like structure formation and turbulent mixing models, a dilution factor of 104is assumed (Lupton et al., 1985). Therefore, a potential initial CH4concentration of approximately 0.4 mmol·L?1in the sediments is sufficient to create a plume with the CH4concentrations detected in the CSS bottom waters (approximately 40 nmol·L?1) and the maximum CH4concentration of 2 mmol·L?1in the seafloor over the CSS (Matveeva et al., 2015). Indeed, the Chukchi Sea bottom sediments have been shown to support methanogenesis rates of up to 67 μmol·m?2·d?1(Savvichev et al., 2007). This intensive CH4production in shallow sediment could supply CH4to the bottom waters, resulting in high CH4concentrations (Fenwick et al., 2017). Thus, we suggest that the decomposition of organic carbon from primary production underlies the biogenic formation of CH4in the CSS.

    Table 2 Correlation analysis between ΔCH4 and +, , , , and with Pearson and Spearman models

    Note: **<0.01, indicating all correlations are significant at the 0.01 level.

    Table 3 CH4 concentrations and sources in different areas of the Arctic Ocean

    4 Conclusion

    This work was supported by the Scientific Research Foundation of the Third Institute of Oceanography, MNR (Grant nos. 2022011, 2018031 and 2018024) and the Natural Science Foundation of Fujian Province, China (Grant no. 2020J01102). We appreciate two anonymous reviewers, and Associate Editor Dr. Daiki Nomura for their constructive comments that have further improved the manuscript.

    Bange H W, Bartell U H, Rapsomanikis S, et al. 1994. Methane in the Baltic and North Seas and a reassessment of the marine emissions of methane. Global Biogeochem Cycles, 8(4): 465-480, doi:10.1029/ 94gb02181.

    Bates T S, Kelly K C, Johnson J E, et al. 1996. A reevaluation of the open ocean source of methane to the atmosphere. J Geophys Res, 101(D3): 6953-6961, doi:10.1029/95jd03348.

    Berchet A, Pison I, Crill P M, et al. 2020. Using ship-borne observations of methane isotopic ratio in the Arctic Ocean to understand methane sources in the Arctic. Atmos Chem Phys, 20(6): 3987-3998, doi:10.5194/acp-20-3987-2020.

    Berner R A. 1982. Burial of organic carbon and pyrite sulfur in the modern ocean: its geochemical and environmental significance. Am J Sci, 282(4): 451-473, doi:10.2475/ajs.282.4.451.

    Buffett B, Archer D. 2004. Global inventory of methane clathrate: sensitivity to changes in the deep ocean. Earth Planet Sci Lett, 227(3-4): 185-199, doi:10.1016/j.epsl.2004.09.005.

    Bui O T N, Kameyama S, Kawaguchi Y, et al. 2019. Influence of warm-core eddy on dissolved methane distributions in the southwestern Canada Basin during late summer/early fall 2015. Polar Sci, 22: 100481, doi:10.1016/j.polar.2019.100481.

    Butler J H, Elkins J W. 1991. An automated technique for the measurement of dissolved N2O in natural waters. Mar Chem, 34(1-2): 47-61, doi:10.1016/0304-4203(91)90013-M.

    Chappellaz J, Bluniert T, Raynaud D, et al. 1993. Synchronous changes in atmospheric CH4and Greenland climate between 40 and 8 kyr BP. Nature, 366(6454): 443-445, doi:10.1038/366443a0.

    Cicerone R J, Oremland R S. 1988. Biogeochemical aspects of atmospheric methane. Global Biogeochem Cycles, 2(4): 299-327, doi:10.1029/gb002i004p00299.

    Coachman L K, Aagaard K. 1966. On the water exchange through Bering Strait. Limnol Oceanogr, 11(1): 44-59, doi:10.4319/lo.1966.11.1. 0044.

    Damm E, Mackensen A, Budéus G, et al. 2005. Pathways of methane in seawater: plume spreading in an Arctic shelf environment (SW- Spitsbergen). Cont Shelf Res, 25(12-13): 1453-1472, doi:10.1016/j. csr.2005.03.003.

    Damm E, Schauer U, Rudels B, et al. 2007. Excess of bottom-released methane in an Arctic shelf sea polynya in winter. Cont Shelf Res, 27(12): 1692-1701, doi:10.1016/j.csr.2007.02.003.

    Daniel W, Jochen K. 2005. Recent distribution and accumulation of organic carbon on the continental margin west of Spitsbergen, Geochem Geophy Geosy, 6(9): 117-134, doi:10.1029/2005GC000916.

    Devol A H, Codispoti L A, Christensen J P. 1997. Summer and winter denitrification rates in western Arctic shelf sediments. Cont Shelf Res, 17(9): 1029-1050, doi:10.1016/S0278-4343(97)00003-4.

    Fenwick L, Capelle D, Damm E, et al. 2017. Methane and nitrous oxide distributions across the North American Arctic Ocean during summer, 2015. J Geophys Res, 122(1): 390-412, doi:10.1002/2016JC012493.

    Gentz T, Damm E, Schneider von Deimling J, et al. 2014. A water column study of methane around gas flares located at the West Spitsbergen continental margin. Cont Shelf Res, 72: 107-118, doi:10.1016/j.csr. 2013.07.013.

    Gong D, Pickart R S. 2015. Summertime circulation in the eastern Chukchi Sea. Deep Sea Res Part II Top Stud Oceanogr, 118: 18-31, doi:10.1016/j.dsr2.2015.02.006.

    Gramberg I S, Kulakov Y N, Pogrebitskiy Y Y, et al. 1983. Arctic oil- and gas-bearing superbasin. Paper presented at the 11th World Petroleum Congress, London, UK, August 1983.

    Grebmeier J M, Bluhm B A, Cooper L W, et al. 2015. Ecosystem characteristics and processes facilitating persistent macrobenthic biomass hotspots and associated benthivory in the Pacific Arctic. Prog Oceanogr, 136: 92-114, doi:10.1016/j.pocean.2015.05.006.

    Grebmeier J M, Cooper L W, Feder H M, et al. 2006. Ecosystem dynamics of the Pacific-influenced northern Bering and Chukchi Seas in the Amerasian Arctic. Prog Oceanogr, 71(2-4): 331-361, doi:10.1016/j. pocean.2006.10.001.

    Henrichs S M, Reeburgh W S. 1987. Anaerobic mineralization of marine sediment organic matter: rates and the role of anaerobic processes in the oceanic carbon economy. Geomicrobiol J, 5(3-4): 191-237, doi:10.1080/01490458709385971.

    Holland M M, Bitz C M. 2003. Polar amplification of climate change in coupled models. Clim Dyn, 21(3): 221-232, doi:10.1007/s00382- 003-0332-6.

    Intergovernmental Panel on Climate Change (IPCC). 2007. Climate change 2007–the physical science basis: Working Group I contribution to the fourth assessment report of the IPCC. Cambridge: Cambridge University Press.

    Ivanov M V, Pimenov N V, Rusanov I I, et al. 2002. Microbial processes of the methane cycle at the north-western shelf of the black sea. Estuar Coast Shelf Sci, 54(3): 589-599, doi:10.1006/ecss.2000.0667.

    Knies J, Damm E, Gutt J, et al. 2004. Near-surface hydrocarbon anomalies in shelf sediments off Spitsbergen: evidences for past seepages. Geochem Geophys Geosyst, 5(6): 135112194, doi:10.1029/2003gc 000687.

    Kudo K, Toyoda S, Yamada K, et al. 2022. Source analysis of dissolved methane in Chukchi Sea and Bering Strait during summer–autumn of 2012 and 2013. Mar Chem, 243: 104119, doi:10.1016/j.marchem. 2022.104119.

    Kudo K, Yamada K, Toyoda S, et al. 2018. Spatial distribution of dissolved methane and its source in the western Arctic Ocean. J Oceanogr, 74(3): 305-317, doi:10.1007/s10872-017-0460-y.

    Kvenvolden K A, Lilley M D, Lorenson T D, et al. 1993. The Beaufort Sea continental shelf as a seasonal source of atmospheric methane. Geophys Res Lett, 20(22): 2459-2462, doi:10.1029/93gl02727.

    Kvenvolden K A, Rogers B W. 2005. Gaia’s breath—global methane exhalations. Mar Petroleum Geol, 22(4): 579-590, doi:10.1016/j. marpetgeo.2004.08.004.

    Lammers S, Suess E, Hovland M. 1995. A large methane plume east of Bear Island (Barents Sea): implications for the marine methane cycle. Geol Rundsch, 84(1): 59-66, doi:10.1007/BF00192242.

    Lapham L, Marshall K, Magen C, et al. 2017. Dissolved methane concentrations in the water column and surface sediments of Hanna Shoal and Barrow Canyon, Northern Chukchi Sea. Deep Sea Res Part II Top Stud Oceanogr, 144: 92-103, doi:10.1016/j.dsr2.2017.01.004.

    Lepore K, Moran S B, Grebmeier J M, et al. 2007. Seasonal and interannual changes in particulate organic carbon export and deposition in the Chukchi Sea. J Geophys Res, 112(C10): C10024, doi:10.1029/2006jc003555.

    Li Y, Zhan L, Zhang J, et al. 2017. A significant methane source over the Chukchi Sea shelf and its sources. Cont Shelf Res, 148: 150-158, doi:10.1016/j.csr.2017.08.019.

    Lupton J E, Delaney J R, Johnson H P, et al. 1985. Entrainment and vertical transport of deep-ocean water by buoyant hydrothermal plumes. Nature, 316(6029): 621-623, doi:10.1038/316621a0.

    Matveeva T, Savvichev A, Semenova A, et al. 2015. Source, origin, and spatial distribution of shallow sediment methane in the Chukchi Sea. Oceanography, 28(3): 202-217, doi:10.5670/oceanog.2015.66.

    Moran S B, Kelly R P, Hagstrom K, et al. 2005. Seasonal changes in POC export flux in the Chukchi Sea and implications for water column-benthic coupling in Arctic shelves. Deep Sea Res Part II Top Stud Oceanogr, 52(24-26): 3427-3451, doi:10.1016/j.dsr2.2005. 09.011.

    Nishino S, Kikuchi T, Fujiwara A, et al. 2016. Water mass characteristics and their temporal changes in a biological hotspot in the southern Chukchi Sea. Biogeosciences, 13(8): 2563-2578, doi:10.5194/bg-13- 2563-2016.

    Reeburgh W S. 2007. Oceanic methane biogeochemistry. Chem Rev, 107(2): 486-513, doi:10.1021/cr050362v.

    Ruppel C. 2015. Permafrost-associated gas hydrate: Is it really approximately 1% of the global system? J Chem Eng Data, 60(2): 429-436, doi:10.1021/je500770m.

    Savvichev A S, Rusanov I I, Iusupov S K, et al. 2004. The biogeochemical cycle of methane in the coastal zone and littoral of the Kandalaksha Bay of the White Sea. Mikrobiologiia, 73(4): 540-552.

    Savvichev A S, Rusanov I I, Pimenov N V, et al. 2007. Microbial processes of the carbon and sulfur cycles in the Chukchi Sea. Microbiology, 76(5): 603-613, doi:10.1134/s0026261707050141.

    Shakhova N, Semiletov I. 2007. Methane release and coastal environment in the East Siberian Arctic shelf. J Mar Syst, 66(1-4): 227-243, doi:10.1016/j.jmarsys.2006.06.006.

    Shakhova N, Semiletov I, Salyuk A, et al. 2010. Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf. Science, 327(5970): 1246-1250, doi:10.1126/science.1182221.

    Spall M A. 2007. Circulation and water mass transformation in a model of the Chukchi Sea. J Geophys Res, 112(C5): C05025, doi:10.1029/ 2005jc003364.

    Steinbach J, Holmstrand H, Shcherbakova K, et al. 2021. Source apportionment of methane escaping the subsea permafrost system in the outer Eurasian Arctic Shelf. Proc Natl Acad Sci, 118(10): e2019672118, doi:10.1073/pnas.2019672118.

    Walsh J J, McRoy C P, Coachman L K, et al. 1989. Carbon and nitrogen cycling within the Bering/Chukchi Seas: source regions for organic matter effecting AOU demands of the Arctic Ocean. Prog Oceanogr, 22(4): 277-359, doi:10.1016/0079-6611(89)90006-2.

    Weber T, Wiseman N A, Kock A. 2019. Global ocean methane emissions dominated by shallow coastal waters. Nat Commun, 10: 4584, doi:10.1038/s41467-019-12541-7.

    Weingartner T, Aagaard K, Woodgate R, et al. 2005. Circulation on the north central Chukchi Sea shelf. Deep Sea Res Part II Top Stud Oceanogr, 52(24-26): 3150-3174, doi:10.1016/j.dsr2.2005.10.015.

    Weingartner T J, Cavalieri D J, Aagaard K, et al. 1998. Circulation, dense water formation, and outflow on the northeast Chukchi Shelf. J Geophys Res, 103(C4): 7647-7661, doi:10.1029/98jc00374.

    Westbrook G K, Thatcher K E, Rohling E J, et al. 2009. Escape of methane gas from the seabed along the West Spitsbergen continental margin. Geophys Res Lett, 36(15): L15608, doi:10.1029/2009gl039191.

    Whiticar M J, Faber E. 1986. Methane oxidation in sediment and water column environments—isotope evidence. Org Geochem, 10(4-6): 759-768, doi:10.1016/S0146-6380(86)80013-4.

    Wiesenburg D A, Guinasso N L. 1979. Equilibrium solubilities of methane, carbon monoxide, and hydrogen in water and sea water. J Chem Eng Data, 24(4): 356-360, doi:10.1021/je60083a006.

    Winkelmann D, Knies J. 2005. Recent distribution and accumulation of organic carbon on the continental margin west off Spitsbergen. Geochem Geophys Geosyst, 6(9): 117-134, doi:10.1029/2005 gc000916.

    Woodgate R A, Aagaard K, Weingartner T J. 2005. A year in the physical oceanography of the Chukchi Sea: moored measurements from autumn 1990–1991. Deep Sea Res Part II Top Stud Oceanogr, 52(24-26): 3116-3149, doi:10.1016/j.dsr2.2005.10.016.

    10.13679/j.advps.2022.0095

    1 July 2022;

    7 September 2022;

    30 September 2022

    : Li Y H, Zhang J X, Ye W W, et al. Concentration maxima of methane in the bottom waters over the Chukchi Sea shelf: implication of its biogenic source. Adv Polar Sci, 2022, 33(3): 235-243,doi:10.13679/j.advps.2022.0095

    , ORCID: 0000-0002-1380-453X, E-mail: zhanliyang@tio.org.cn

    日韩亚洲欧美综合| 在线观看国产h片| 交换朋友夫妻互换小说| 麻豆成人av视频| 免费黄色在线免费观看| 国产黄片视频在线免费观看| 日日啪夜夜撸| 国产成人freesex在线| videos熟女内射| 亚洲欧美中文字幕日韩二区| 又粗又硬又长又爽又黄的视频| 精品国产一区二区三区久久久樱花| 91成人精品电影| 51国产日韩欧美| 国产黄片视频在线免费观看| 亚洲av.av天堂| 久久久久久久久久人人人人人人| 99热这里只有精品一区| 黄色怎么调成土黄色| 国产永久视频网站| 亚洲高清免费不卡视频| 成人国产av品久久久| 大片免费播放器 马上看| 少妇猛男粗大的猛烈进出视频| av国产久精品久网站免费入址| 我要看黄色一级片免费的| 简卡轻食公司| 建设人人有责人人尽责人人享有的| 18禁动态无遮挡网站| 久久精品国产鲁丝片午夜精品| 男人添女人高潮全过程视频| 午夜免费男女啪啪视频观看| 波野结衣二区三区在线| 中文天堂在线官网| 黑人猛操日本美女一级片| 老司机影院成人| 久久久a久久爽久久v久久| 老司机影院毛片| 99久久精品热视频| 夜夜骑夜夜射夜夜干| 国产乱人偷精品视频| 亚洲中文av在线| 日本av免费视频播放| 我要看日韩黄色一级片| 亚洲国产成人一精品久久久| 精品国产一区二区三区久久久樱花| 极品人妻少妇av视频| 久久国产亚洲av麻豆专区| 久热久热在线精品观看| 亚洲av二区三区四区| 少妇被粗大猛烈的视频| 99九九在线精品视频 | 97超视频在线观看视频| 国产精品熟女久久久久浪| 国产高清三级在线| 91久久精品电影网| 成人影院久久| 日韩一区二区三区影片| 不卡视频在线观看欧美| 一区二区av电影网| 99久国产av精品国产电影| av在线老鸭窝| 亚洲av欧美aⅴ国产| 一级片'在线观看视频| 国产精品熟女久久久久浪| 久久久久久久亚洲中文字幕| 伊人亚洲综合成人网| 精品久久久久久久久av| 人妻系列 视频| 亚洲精华国产精华液的使用体验| 欧美日韩视频精品一区| 嫩草影院入口| 大又大粗又爽又黄少妇毛片口| 国产精品一区二区性色av| 免费不卡的大黄色大毛片视频在线观看| 欧美日韩国产mv在线观看视频| 久久久久久久久久久丰满| 久久久国产精品麻豆| 免费播放大片免费观看视频在线观看| 最近手机中文字幕大全| 日韩一区二区视频免费看| av网站免费在线观看视频| 欧美国产精品一级二级三级 | 欧美日韩精品成人综合77777| 最近中文字幕高清免费大全6| 美女视频免费永久观看网站| .国产精品久久| 亚洲怡红院男人天堂| 美女内射精品一级片tv| 国产日韩欧美在线精品| 在线观看av片永久免费下载| 99九九线精品视频在线观看视频| 国产美女午夜福利| 在线精品无人区一区二区三| 国内揄拍国产精品人妻在线| 男人和女人高潮做爰伦理| 丝袜喷水一区| 国产女主播在线喷水免费视频网站| 国产成人精品婷婷| 国产亚洲一区二区精品| av福利片在线观看| 日韩三级伦理在线观看| 一级黄片播放器| 欧美老熟妇乱子伦牲交| 人人妻人人澡人人看| 王馨瑶露胸无遮挡在线观看| 男人添女人高潮全过程视频| 久久国产乱子免费精品| 亚洲综合精品二区| av视频免费观看在线观看| 亚洲精品久久久久久婷婷小说| 欧美性感艳星| 特大巨黑吊av在线直播| .国产精品久久| 亚洲一级一片aⅴ在线观看| 国内精品宾馆在线| a级片在线免费高清观看视频| 街头女战士在线观看网站| 久久久久久久精品精品| 99久久人妻综合| 熟女电影av网| 亚洲精品国产色婷婷电影| 久久99热6这里只有精品| 亚洲在久久综合| 精品国产乱码久久久久久小说| 嫩草影院入口| 精品一品国产午夜福利视频| 日本午夜av视频| 男男h啪啪无遮挡| 精品亚洲成国产av| 这个男人来自地球电影免费观看 | 婷婷色av中文字幕| 国产成人freesex在线| 精品久久久久久电影网| 亚洲国产最新在线播放| 特大巨黑吊av在线直播| 天天操日日干夜夜撸| 26uuu在线亚洲综合色| 欧美性感艳星| 十八禁高潮呻吟视频 | 啦啦啦啦在线视频资源| 成年美女黄网站色视频大全免费 | 97精品久久久久久久久久精品| 两个人免费观看高清视频 | 精品99又大又爽又粗少妇毛片| 啦啦啦中文免费视频观看日本| 亚洲不卡免费看| 你懂的网址亚洲精品在线观看| 一边亲一边摸免费视频| 免费看日本二区| 亚洲av二区三区四区| 777米奇影视久久| 最近2019中文字幕mv第一页| 人人妻人人爽人人添夜夜欢视频 | 麻豆精品久久久久久蜜桃| 少妇被粗大的猛进出69影院 | av有码第一页| 亚洲内射少妇av| 天堂俺去俺来也www色官网| 欧美激情极品国产一区二区三区 | 3wmmmm亚洲av在线观看| 成年人午夜在线观看视频| 亚洲无线观看免费| 日本vs欧美在线观看视频 | 国产 一区精品| 成人无遮挡网站| 日韩电影二区| 99热国产这里只有精品6| 性色avwww在线观看| 赤兔流量卡办理| 亚洲天堂av无毛| 日韩欧美精品免费久久| 国产成人一区二区在线| 国产国拍精品亚洲av在线观看| 人妻系列 视频| 亚洲av二区三区四区| 久久久国产一区二区| 麻豆精品久久久久久蜜桃| .国产精品久久| 男女边吃奶边做爰视频| 精品亚洲成a人片在线观看| 欧美精品人与动牲交sv欧美| 国产精品久久久久久av不卡| 国产成人午夜福利电影在线观看| 18禁裸乳无遮挡动漫免费视频| 国产精品99久久99久久久不卡 | 久久精品国产自在天天线| 亚洲四区av| 伦精品一区二区三区| 99久久中文字幕三级久久日本| 精品人妻熟女av久视频| 人妻制服诱惑在线中文字幕| 自拍欧美九色日韩亚洲蝌蚪91 | 十分钟在线观看高清视频www | 亚洲av日韩在线播放| 一级毛片电影观看| 久久久久久久久久久丰满| 亚洲第一区二区三区不卡| 又大又黄又爽视频免费| 黄色视频在线播放观看不卡| 久久av网站| 亚洲精品乱码久久久久久按摩| 亚洲欧美日韩卡通动漫| 少妇被粗大的猛进出69影院 | 精品国产一区二区三区久久久樱花| 97在线视频观看| 中文字幕亚洲精品专区| 制服丝袜香蕉在线| 精品少妇内射三级| 国产伦在线观看视频一区| 国产成人免费观看mmmm| 三上悠亚av全集在线观看 | 免费看日本二区| 亚洲欧美精品自产自拍| 卡戴珊不雅视频在线播放| 夜夜爽夜夜爽视频| 色婷婷av一区二区三区视频| 亚洲成人一二三区av| 免费观看在线日韩| 日日摸夜夜添夜夜爱| 亚洲三级黄色毛片| 精品久久久久久电影网| 建设人人有责人人尽责人人享有的| 久久国产精品大桥未久av | 国产又色又爽无遮挡免| 久久久久视频综合| 国产爽快片一区二区三区| 国产永久视频网站| 亚洲国产最新在线播放| 国产精品人妻久久久久久| 国产一区二区在线观看av| 亚洲精品第二区| 黄色日韩在线| 午夜免费鲁丝| 极品少妇高潮喷水抽搐| 男女啪啪激烈高潮av片| 欧美 亚洲 国产 日韩一| 国产伦在线观看视频一区| 国产一区亚洲一区在线观看| 高清毛片免费看| 日韩av不卡免费在线播放| 男男h啪啪无遮挡| 97超碰精品成人国产| 亚洲综合色惰| 国产一级毛片在线| 午夜福利网站1000一区二区三区| av国产久精品久网站免费入址| 日韩成人伦理影院| 爱豆传媒免费全集在线观看| 蜜桃久久精品国产亚洲av| 日韩一本色道免费dvd| 久久久久久久精品精品| 国产伦理片在线播放av一区| 成人特级av手机在线观看| 亚洲图色成人| freevideosex欧美| 我要看黄色一级片免费的| 成年人免费黄色播放视频 | 精品亚洲成国产av| 国产精品秋霞免费鲁丝片| 99热这里只有是精品在线观看| 欧美xxⅹ黑人| 国产精品久久久久久av不卡| 亚洲无线观看免费| 色哟哟·www| 亚洲图色成人| 久久精品久久久久久噜噜老黄| 亚洲欧美日韩另类电影网站| 国产成人精品无人区| 在线观看免费高清a一片| 少妇的逼水好多| 我的女老师完整版在线观看| 久久久久久久久久久丰满| 欧美日韩在线观看h| 久久久久网色| 亚洲欧美一区二区三区黑人 | 人妻夜夜爽99麻豆av| 美女福利国产在线| 黄色配什么色好看| 日本爱情动作片www.在线观看| 少妇的逼水好多| 黑人高潮一二区| 内地一区二区视频在线| 少妇被粗大猛烈的视频| 如何舔出高潮| 成人黄色视频免费在线看| 亚洲国产色片| 欧美xxⅹ黑人| videossex国产| 在线精品无人区一区二区三| 国产av码专区亚洲av| 日本爱情动作片www.在线观看| 国产av一区二区精品久久| 久久久久视频综合| 少妇精品久久久久久久| 精品一区二区免费观看| 黑人巨大精品欧美一区二区蜜桃 | 边亲边吃奶的免费视频| 在现免费观看毛片| 大话2 男鬼变身卡| 在现免费观看毛片| 寂寞人妻少妇视频99o| av国产久精品久网站免费入址| 欧美日本中文国产一区发布| 男女国产视频网站| 久久婷婷青草| 中文精品一卡2卡3卡4更新| 国产日韩欧美亚洲二区| 日本wwww免费看| 国产精品久久久久久精品古装| 在线观看av片永久免费下载| 男人爽女人下面视频在线观看| av福利片在线观看| 国模一区二区三区四区视频| 五月开心婷婷网| 天堂8中文在线网| 国产伦精品一区二区三区四那| 丰满人妻一区二区三区视频av| 在线亚洲精品国产二区图片欧美 | 国产av国产精品国产| 日日摸夜夜添夜夜添av毛片| 久久ye,这里只有精品| 中文在线观看免费www的网站| 亚洲欧美成人综合另类久久久| 啦啦啦啦在线视频资源| 国产精品无大码| 少妇熟女欧美另类| 国产亚洲5aaaaa淫片| 丝袜脚勾引网站| 成年美女黄网站色视频大全免费 | 在线观看一区二区三区激情| av又黄又爽大尺度在线免费看| 涩涩av久久男人的天堂| 色婷婷av一区二区三区视频| 乱码一卡2卡4卡精品| 少妇丰满av| 晚上一个人看的免费电影| 在线观看免费日韩欧美大片 | 欧美3d第一页| 亚洲一区二区三区欧美精品| 国产成人aa在线观看| 亚洲国产日韩一区二区| 搡老乐熟女国产| 欧美变态另类bdsm刘玥| 国产高清国产精品国产三级| 色5月婷婷丁香| 国产亚洲最大av| 久热这里只有精品99| 日本猛色少妇xxxxx猛交久久| av在线老鸭窝| 中文精品一卡2卡3卡4更新| 国产精品麻豆人妻色哟哟久久| 中国三级夫妇交换| 精品久久久噜噜| 亚洲一级一片aⅴ在线观看| 中文字幕人妻熟人妻熟丝袜美| 亚洲av成人精品一二三区| 99热这里只有精品一区| 少妇人妻久久综合中文| av黄色大香蕉| 我的女老师完整版在线观看| 精品久久久噜噜| 在线观看三级黄色| 欧美97在线视频| 黑人高潮一二区| 欧美精品高潮呻吟av久久| 亚洲av.av天堂| 91成人精品电影| 十分钟在线观看高清视频www | 视频区图区小说| 免费黄网站久久成人精品| 日韩不卡一区二区三区视频在线| 精品人妻一区二区三区麻豆| 黑人高潮一二区| 日本欧美视频一区| av又黄又爽大尺度在线免费看| 在线观看人妻少妇| 国产欧美另类精品又又久久亚洲欧美| 日韩视频在线欧美| 精品午夜福利在线看| 欧美精品高潮呻吟av久久| 最近最新中文字幕免费大全7| 极品少妇高潮喷水抽搐| 七月丁香在线播放| 久久久久久久亚洲中文字幕| 97超视频在线观看视频| 国产色婷婷99| 国产国拍精品亚洲av在线观看| 欧美一级a爱片免费观看看| av免费在线看不卡| 久久久国产欧美日韩av| 各种免费的搞黄视频| 免费黄频网站在线观看国产| 日日撸夜夜添| 精品亚洲成a人片在线观看| 亚洲国产精品专区欧美| 免费黄频网站在线观看国产| 精品午夜福利在线看| 亚洲第一av免费看| 国产精品人妻久久久影院| 在线观看人妻少妇| 中文精品一卡2卡3卡4更新| 亚洲第一av免费看| 午夜久久久在线观看| 男女无遮挡免费网站观看| 亚洲国产欧美在线一区| 秋霞伦理黄片| 搡老乐熟女国产| 日韩在线高清观看一区二区三区| 中国国产av一级| 在线播放无遮挡| 欧美性感艳星| 人妻制服诱惑在线中文字幕| 嫩草影院入口| 制服丝袜香蕉在线| 曰老女人黄片| 日韩av不卡免费在线播放| 免费黄色在线免费观看| av播播在线观看一区| 免费看av在线观看网站| 人人妻人人澡人人看| 新久久久久国产一级毛片| 在线观看三级黄色| 18+在线观看网站| 国产综合精华液| 亚洲欧美日韩东京热| 大片免费播放器 马上看| 日本免费在线观看一区| 丝袜脚勾引网站| 蜜臀久久99精品久久宅男| 国产69精品久久久久777片| 少妇被粗大猛烈的视频| 免费黄频网站在线观看国产| 97在线视频观看| 久久av网站| 久久 成人 亚洲| 美女脱内裤让男人舔精品视频| 色婷婷久久久亚洲欧美| av在线观看视频网站免费| 男人狂女人下面高潮的视频| 国产精品秋霞免费鲁丝片| 国产精品麻豆人妻色哟哟久久| 午夜久久久在线观看| 亚洲无线观看免费| 亚洲高清免费不卡视频| 永久免费av网站大全| 三级国产精品片| 成人黄色视频免费在线看| 亚洲精品乱码久久久v下载方式| 一本色道久久久久久精品综合| 成人综合一区亚洲| 欧美国产精品一级二级三级 | 一区二区三区乱码不卡18| 午夜福利网站1000一区二区三区| 国产美女午夜福利| 精华霜和精华液先用哪个| 伊人久久国产一区二区| √禁漫天堂资源中文www| 秋霞伦理黄片| 国产黄片视频在线免费观看| 一级毛片黄色毛片免费观看视频| 欧美日韩av久久| av在线观看视频网站免费| 国产91av在线免费观看| 亚洲美女视频黄频| 亚洲av成人精品一区久久| √禁漫天堂资源中文www| 欧美激情国产日韩精品一区| 最后的刺客免费高清国语| 日日撸夜夜添| 午夜视频国产福利| 国产黄片视频在线免费观看| 肉色欧美久久久久久久蜜桃| 国产日韩欧美视频二区| 又大又黄又爽视频免费| 久久狼人影院| 一级二级三级毛片免费看| 久久久国产精品麻豆| 在线 av 中文字幕| 久久99精品国语久久久| 精品亚洲乱码少妇综合久久| 国产男女内射视频| 国产一区二区三区综合在线观看 | 免费观看性生交大片5| .国产精品久久| 亚洲精品国产av成人精品| 亚洲精品乱码久久久久久按摩| 如何舔出高潮| xxx大片免费视频| 免费看不卡的av| 久久97久久精品| 午夜福利在线观看免费完整高清在| 国产精品99久久99久久久不卡 | 美女福利国产在线| 欧美精品一区二区大全| 欧美丝袜亚洲另类| 最近最新中文字幕免费大全7| 亚洲人成网站在线观看播放| 热re99久久国产66热| 亚洲国产精品一区二区三区在线| 国产精品一二三区在线看| 亚洲伊人久久精品综合| 欧美变态另类bdsm刘玥| 91精品伊人久久大香线蕉| 成人毛片60女人毛片免费| 天堂俺去俺来也www色官网| 少妇人妻久久综合中文| 欧美高清成人免费视频www| 亚洲成人手机| 日韩av在线免费看完整版不卡| 欧美成人精品欧美一级黄| 成人国产av品久久久| 亚洲欧美精品自产自拍| 热re99久久精品国产66热6| 桃花免费在线播放| 熟女av电影| 丰满少妇做爰视频| 国产精品国产三级专区第一集| 国产爽快片一区二区三区| 亚洲内射少妇av| 黄色一级大片看看| 亚洲av免费高清在线观看| 91aial.com中文字幕在线观看| 久久久国产欧美日韩av| 久久人人爽av亚洲精品天堂| 人体艺术视频欧美日本| 建设人人有责人人尽责人人享有的| 日本vs欧美在线观看视频 | 国产精品久久久久久av不卡| 国产永久视频网站| 亚洲精品乱码久久久v下载方式| √禁漫天堂资源中文www| 女性生殖器流出的白浆| 国产黄色视频一区二区在线观看| 午夜av观看不卡| 日本91视频免费播放| 亚洲精品国产色婷婷电影| av天堂中文字幕网| 国产乱来视频区| 亚洲国产精品专区欧美| 中国美白少妇内射xxxbb| 亚洲综合精品二区| 欧美精品一区二区免费开放| 国产成人精品一,二区| 一级毛片久久久久久久久女| 精品国产露脸久久av麻豆| 亚洲欧美日韩另类电影网站| 亚洲av男天堂| 高清视频免费观看一区二区| 美女cb高潮喷水在线观看| 国产一区二区三区av在线| 免费少妇av软件| 国产av国产精品国产| 国内少妇人妻偷人精品xxx网站| 内地一区二区视频在线| 久久ye,这里只有精品| 插逼视频在线观看| 久久99热6这里只有精品| 亚洲精品色激情综合| 国产在线视频一区二区| 欧美日韩av久久| 搡女人真爽免费视频火全软件| 久久毛片免费看一区二区三区| 午夜91福利影院| 街头女战士在线观看网站| 亚洲第一av免费看| 久久 成人 亚洲| 亚洲av中文av极速乱| 在线观看人妻少妇| 精品少妇久久久久久888优播| 纵有疾风起免费观看全集完整版| 高清毛片免费看| 久久影院123| 欧美xxⅹ黑人| 精品99又大又爽又粗少妇毛片| a级毛片免费高清观看在线播放| 欧美日韩综合久久久久久| 热re99久久精品国产66热6| 欧美精品国产亚洲| 黄色配什么色好看| 少妇人妻精品综合一区二区| 九九久久精品国产亚洲av麻豆| 亚洲国产精品999| 国产精品嫩草影院av在线观看| 国内揄拍国产精品人妻在线| 在线播放无遮挡| 在现免费观看毛片| 日韩不卡一区二区三区视频在线| 欧美老熟妇乱子伦牲交| 亚洲av免费高清在线观看| 又大又黄又爽视频免费| 97超碰精品成人国产| 大香蕉97超碰在线| 精华霜和精华液先用哪个| av视频免费观看在线观看| 国产在视频线精品| 精品久久久久久久久亚洲| a级一级毛片免费在线观看| 一区二区三区免费毛片| 国产真实伦视频高清在线观看| 久久精品熟女亚洲av麻豆精品| 91精品国产国语对白视频| 久久99精品国语久久久| 男人添女人高潮全过程视频| 亚洲经典国产精华液单| 在线观看三级黄色| 久久久久久久久久久免费av| 韩国高清视频一区二区三区| 国产欧美另类精品又又久久亚洲欧美| h视频一区二区三区| 嫩草影院入口| 91aial.com中文字幕在线观看| 秋霞伦理黄片| 美女cb高潮喷水在线观看| 久久久久精品久久久久真实原创|